Sorry for the poor pic. I just used my phone. You will see the open caseback of the MM25. What is on now is the anti-magnetic plate. I can't get past this. Its really a tight fit and i can't find the seams. That hole allows access to a small screw that when loosened takes out the stem. The anti magnetic plate won't fall off and forcing it open will surely damage the metal.
If you have any ideas please let me know.